Monolayer MoS2 Fabricated by In Situ Construction of Interlayer Electrostatic Repulsion Enables Ultrafast Ion Transport in Lithium-Ion Batteries

Meisheng Han; Yongbiao Mu; Jincong Guo; Lei Wei; Lin Zeng; Tianshou Zhao

doi:10.1007/s40820-023-01042-4

Monolayer MoS₂ Fabricated by In Situ Construction of Interlayer Electrostatic Repulsion Enables Ultrafast Ion Transport in Lithium-Ion Batteries

Nanomicro Lett. 2023 Mar 31;15(1):80. doi: 10.1007/s40820-023-01042-4.

Authors

Meisheng Han¹, Yongbiao Mu¹, Jincong Guo¹, Lei Wei¹, Lin Zeng¹, Tianshou Zhao²

Affiliations

¹ Shenzhen Key Laboratory of Advanced Energy Storage, Department of Mechanical and Energy Engineering, SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, 518055, People's Republic of China.
² Shenzhen Key Laboratory of Advanced Energy Storage, Department of Mechanical and Energy Engineering, SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, 518055, People's Republic of China. zhaots@sustech.edu.cn.

Abstract

Highlights:

In-situ construction of electrostatic repulsion between MoS₂ interlayers is first proposed to successfully prepare Co-doped monolayer MoS₂ under high vapor pressure.
The doped Co atoms radically decrease bandgap and lithium ion diffusion energy barrier of monolayer MoS₂ and can be transformed into ultrasmall Co nanoparticles (~2 nm) to induce strong surface-capacitance effect during conversion reaction.
The Co doped monolayer MoS₂ shows ultrafast ion transport capability along with ultrahigh capacity and outstanding cycling stability as lithium-ion-battery anodes.

Abstract: High theoretical capacity and unique layered structures make MoS₂ a promising lithium-ion battery anode material. However, the anisotropic ion transport in layered structures and the poor intrinsic conductivity of MoS₂ lead to unacceptable ion transport capability. Here, we propose in-situ construction of interlayer electrostatic repulsion caused by Co²+ substituting Mo⁴⁺ between MoS₂ layers, which can break the limitation of interlayer van der Waals forces to fabricate monolayer MoS₂, thus establishing isotropic ion transport paths. Simultaneously, the doped Co atoms change the electronic structure of monolayer MoS₂, thus improving its intrinsic conductivity. Importantly, the doped Co atoms can be converted into Co nanoparticles to create a space charge region to accelerate ion transport. Hence, the Co-doped monolayer MoS₂ shows ultrafast lithium ion transport capability in half/full cells. This work presents a novel route for the preparation of monolayer MoS₂ and demonstrates its potential for application in fast-charging lithium-ion batteries.

Supplementary Information: The online version contains supplementary material available at 10.1007/s40820-023-01042-4.

Keywords: Co atoms doping; Fast-charging lithium-ion batteries; Interlayer electrostatic repulsion; Monolayer MoS2; Surface-capacitance effect.